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Semsirmboon S, Nguyen DKD, Chaiyabutr N, Poonyachoti S, Thammacharoen S. Natural high ambient temperature-induced respiratory hypocapnia without activation of the hypothalamic-pituitary-adrenal axis in lactating goats. Vet World 2022; 15:2611-2616. [PMID: 36590112 PMCID: PMC9798072 DOI: 10.14202/vetworld.2022.2611-2616] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2022] [Accepted: 10/06/2022] [Indexed: 11/21/2022] Open
Abstract
Background and Aim Activation of breathing, the hypothalamic-pituitary-adrenal (HPA) axis, and plasma antioxidant defense are adaptive mechanisms in lactating dairy goats fed during the summer season. However, an excess of these responses can interfere with the gas exchange. This study aimed to investigate the effect of natural high ambient temperature (HTa) on blood gas parameters and their relation to the HPA axis and antioxidant defense. Materials and Methods Six mid-lactating goats were included in this study and were fed in individual pens for 2 weeks. The data on ambient conditions, physiological responses, and blood chemistry were measured for two sampling days (D7 and D14), 1 week apart during the late summer season. On this two-sampling day, the main physiological responses to HTa, including respiration rate (RR), rectal temperature (Tr), blood gas, and blood chemistry, were measured in the morning and afternoon. Results Goats from both D7 and D14 increased RR and Tr significantly according to morning and afternoon periods. In addition, goats were at the hypocapnia stage during afternoon panting without a change in blood pH and bicarbonate levels. Interestingly, HTa-induced hypocapnia was not accompanied by an increase in plasma cortisol levels. Finally, ΔTa was negatively correlated with changes in glutathione peroxidase activity. Conclusion The natural HTa (ΔTa; 5-8°C) in this study activated evaporative heat dissipation and was high enough to induce respiratory hypocapnia. Importantly, this ΔTa did not activate the HPA axis but was correlated with a change in antioxidant defense. Therefore, under natural HTa in tropical conditions, respiratory hypocapnia is the first line of physiological response in goats within a specific range of natural ΔTa (5-8°C).
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Affiliation(s)
- Sapon Semsirmboon
- Department of Physiology, Faculty of Veterinary Science, Chulalongkorn University, Pathumwan, Bangkok 10330, Thailand
| | - Dang Khoa Do Nguyen
- Department of Physiology, Faculty of Veterinary Science, Chulalongkorn University, Pathumwan, Bangkok 10330, Thailand
| | - Narongsak Chaiyabutr
- Department of Physiology, Faculty of Veterinary Science, Chulalongkorn University, Pathumwan, Bangkok 10330, Thailand,The Academy of Science, The Royal Society of Thailand, Dusit, Bangkok 10300, Thailand,Queen Saovabha Memorial Institute, The Thai Red Cross Society, Bangkok 10330, Thailand
| | - Sutthasinee Poonyachoti
- Department of Physiology, Faculty of Veterinary Science, Chulalongkorn University, Pathumwan, Bangkok 10330, Thailand
| | - Sumpun Thammacharoen
- Department of Physiology, Faculty of Veterinary Science, Chulalongkorn University, Pathumwan, Bangkok 10330, Thailand,Corresponding author: Sumpun Thammacharoen, e-mail: Co-authors: SS: , DKDN: , NC: , SP:
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Hoenig MP, Lecker SH, William JH. What's Old Is New Again: Harnessing the Power of Original Experiments to Learn Renal Physiology. Adv Chronic Kidney Dis 2022; 29:486-492. [PMID: 36371110 DOI: 10.1053/j.ackd.2022.03.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2021] [Revised: 03/02/2022] [Accepted: 03/22/2022] [Indexed: 11/10/2022]
Abstract
Although medical schools across the United States have updated their curricula to incorporate active learning techniques, there has been little discussion on the nature of the content presented to students. Here, we share detailed examples of our experience in using original experiments to lay the groundwork for foundational concepts in renal physiology and pathophysiology. We believe that this approach offers distinct advantages over standard case-based teaching by (1) starting with simple concepts, (2) analyzing memorable visuals, (3) increasing graphical literacy, (4) translating observations to "rules," (5) encouraging critical thinking, and (6) providing historical perspective to the study of medicine. Although we developed this content for medical students, we have found that many of these lessons are also appropriate as foundational concepts for residents and fellows and serve as an excellent springboard for increasingly complex discussions of clinical applications of physiology. The use of original experiments for teaching and learning in renal physiology harnesses skills in critical thinking and provides a solid foundation that will help learners with subsequent case-based learning in the preclerkship curriculum and in the clinical arena.
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Affiliation(s)
- Melanie P Hoenig
- Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA.
| | - Stewart H Lecker
- Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA
| | - Jeffrey H William
- Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA
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Caldwell HG, Carr JMJR, Minhas JS, Swenson ER, Ainslie PN. Acid-base balance and cerebrovascular regulation. J Physiol 2021; 599:5337-5359. [PMID: 34705265 DOI: 10.1113/jp281517] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2021] [Accepted: 10/19/2021] [Indexed: 12/22/2022] Open
Abstract
The regulation and defence of intracellular pH is essential for homeostasis. Indeed, alterations in cerebrovascular acid-base balance directly affect cerebral blood flow (CBF) which has implications for human health and disease. For example, changes in CBF regulation during acid-base disturbances are evident in conditions such as chronic obstructive pulmonary disease and diabetic ketoacidosis. The classic experimental studies from the past 75+ years are utilized to describe the integrative relationships between CBF, carbon dioxide tension (PCO2 ), bicarbonate (HCO3 - ) and pH. These factors interact to influence (1) the time course of acid-base compensatory changes and the respective cerebrovascular responses (due to rapid exchange kinetics between arterial blood, extracellular fluid and intracellular brain tissue). We propose that alterations in arterial [HCO3 - ] during acute respiratory acidosis/alkalosis contribute to cerebrovascular acid-base regulation; and (2) the regulation of CBF by direct changes in arterial vs. extravascular/interstitial PCO2 and pH - the latter recognized as the proximal compartment which alters vascular smooth muscle cell regulation of CBF. Taken together, these results substantiate two key ideas: first, that the regulation of CBF is affected by the severity of metabolic/respiratory disturbances, including the extent of partial/full acid-base compensation; and second, that the regulation of CBF is independent of arterial pH and that diffusion of CO2 across the blood-brain barrier is integral to altering perivascular extracellular pH. Overall, by realizing the integrative relationships between CBF, PCO2 , HCO3 - and pH, experimental studies may provide insights to improve CBF regulation in clinical practice with treatment of systemic acid-base disorders.
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Affiliation(s)
- Hannah G Caldwell
- Centre for Heart, Lung and Vascular Health, School of Health and Exercise Sciences, University of British Columbia, Okanagan, Kelowna, Canada
| | - Jay M J R Carr
- Centre for Heart, Lung and Vascular Health, School of Health and Exercise Sciences, University of British Columbia, Okanagan, Kelowna, Canada
| | - Jatinder S Minhas
- Cerebral Haemodynamics in Ageing and Stroke Medicine (CHiASM) Research Group, NIHR Leicester Biomedical Research Centre, University of Leicester, Leicester, UK
| | - Erik R Swenson
- Pulmonary, Critical Care and Sleep Medicine Division, University of Washington, and VA Puget Sound Healthcare System, Seattle, WA, USA
| | - Philip N Ainslie
- Centre for Heart, Lung and Vascular Health, School of Health and Exercise Sciences, University of British Columbia, Okanagan, Kelowna, Canada
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Bader TJ, Leacy JK, Keough JRG, Ciorogariu‐Ivan A, Donald JR, Marullo AL, O’Halloran KD, Jendzjowsky NG, Wilson RJA, Day TA. The effects of acute incremental hypocapnia on the magnitude of neurovascular coupling in healthy participants. Physiol Rep 2021; 9:e14952. [PMID: 34350726 PMCID: PMC8339533 DOI: 10.14814/phy2.14952] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2021] [Accepted: 04/17/2021] [Indexed: 12/03/2022] Open
Abstract
The high metabolic demand of cerebral tissue requires that local perfusion is tightly coupled with local metabolic rate (neurovascular coupling; NVC). During chronic altitude exposure, where individuals are exposed to the antagonistic cerebrovascular effects of hypoxia and hypocapnia, pH is maintained through renal compensation and NVC remains stable. However, the potential independent effect of acute hypocapnia and respiratory alkalosis on NVC remains to be determined. We hypothesized that acute steady-state hypocapnia via voluntary hyperventilation would attenuate the magnitude of NVC. We recruited 17 healthy participants and insonated the posterior cerebral artery (PCA) with transcranial Doppler ultrasound. NVC was elicited using a standardized strobe light stimulus (6 Hz; 5 × 30 s on/off) where absolute delta responses from baseline (BL) in peak, mean, and total area under the curve (tAUC) were quantified. From a BL end-tidal (PET )CO2 level of 36.7 ± 3.2 Torr, participants were coached to hyperventilate to reach steady-state hypocapnic steps of Δ-5 Torr (31.6 ± 3.9) and Δ-10 Torr (26.0 ± 4.0; p < 0.001), which were maintained during the presentation of the visual stimuli. We observed a small but significant reduction in NVC peak (ΔPCAv) from BL during controlled hypocapnia at both Δ-5 (-1.58 cm/s) and Δ-10 (-1.37 cm/s), but no significant decrease in mean or tAUC NVC response was observed. These data demonstrate that acute respiratory alkalosis attenuates peak NVC magnitude at Δ-5 and Δ-10 Torr PET CO2 , equally. Although peak NVC magnitude was mildly attenuated, our data illustrate that mean and tAUC NVC are remarkably stable during acute respiratory alkalosis, suggesting multiple mechanisms underlying NVC.
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Affiliation(s)
- Taylor J. Bader
- Department of BiologyFaculty of Science and TechnologyMount Royal UniversityCalgaryABCanada
| | - Jack K. Leacy
- Department of PhysiologySchool of MedicineCollege of Medicine and HealthUniversity College CorkCorkIreland
| | - Joanna R. G. Keough
- Department of BiologyFaculty of Science and TechnologyMount Royal UniversityCalgaryABCanada
| | | | - Joshua R. Donald
- Department of BiologyFaculty of Science and TechnologyMount Royal UniversityCalgaryABCanada
| | - Anthony L. Marullo
- Department of BiologyFaculty of Science and TechnologyMount Royal UniversityCalgaryABCanada
| | - Ken D. O’Halloran
- Department of PhysiologySchool of MedicineCollege of Medicine and HealthUniversity College CorkCorkIreland
| | - Nicholas G. Jendzjowsky
- Division of Respiratory and Critical Care Physiology and MedicineThe Lundquist Institute for Biomedical Innovation at Harbor‐UCLA Medical CenterTorranceCAUSA
| | - Richard J. A. Wilson
- Department of Physiology and PharmacologyHotchkiss Brain InstituteCumming School of MedicineUniversity of CalgaryCalgaryABCanada
| | - Trevor A. Day
- Department of BiologyFaculty of Science and TechnologyMount Royal UniversityCalgaryABCanada
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Seifter JL, Chang HY. Disorders of Acid-Base Balance: New Perspectives. KIDNEY DISEASES (BASEL, SWITZERLAND) 2017; 2:170-186. [PMID: 28232934 PMCID: PMC5260542 DOI: 10.1159/000453028] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/08/2016] [Revised: 11/26/2016] [Indexed: 11/19/2022]
Abstract
BACKGROUND Disorders of acid-base involve the complex interplay of many organ systems including brain, lungs, kidney, and liver. Compensations for acid-base disturbances within the brain are more complete, while limitations of compensations are more apparent for most systemic disorders. However, some of the limitations on compensations are necessary to survival, in that preservation of oxygenation, energy balance, cognition, electrolyte, and fluid balance are connected mechanistically. SUMMARY This review aims to give new and comprehensive perspective on understanding acid-base balance and identifying associated disorders. All metabolic acid-base disorders can be approached in the context of the relative losses or gains of electrolytes or a change in the anion gap in body fluids. Acid-base and electrolyte balance are connected not only at the cellular level but also in daily clinical practice. Urine chemistry is essential to understanding electrolyte excretion and renal compensations. KEY MESSAGES Many constructs are helpful to understand acid-base, but these models are not mutually exclusive. Electroneutrality and the close interconnection between electrolyte and acid-base balance are important concepts to apply in acid-base diagnoses. All models have complexity and shortcuts that can help in practice. There is no reason to dismiss any of the present constructs, and there is benefit in a combined approach.
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Affiliation(s)
- Julian L. Seifter
- Renal Division, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
| | - Hsin-Yun Chang
- Kaohsiung Medical University Hospital, Kaohsiung, Taiwan, ROC
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Ramadoss J, Stewart RH, Cudd TA. Acute renal response to rapid onset respiratory acidosis. Can J Physiol Pharmacol 2012; 89:227-31. [PMID: 21423296 DOI: 10.1139/y11-008] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Renal strong ion compensation to chronic respiratory acidosis has been established, but the nature of the response to acute respiratory acidosis is not well defined. We hypothesized that the response to acute respiratory acidosis in sheep is a rapid increase in the difference in renal fractional excretions of chloride and sodium (Fe(Cl) - Fe(Na)). Inspired CO(2) concentrations were increased for 1 h to significantly alter P(a)CO(2) and pH(a) from 32 ± 1 mm Hg and 7.52 ± 0.02 to 74 ± 2 mm Hg and 7.22 ± 0.02, respectively. Fe(Cl) - Fe(Na) increased significantly from 0.372 ± 0.206 to 1.240 ± 0.217% and returned to baseline at 2 h when P(a)CO(2) and pH(a) were 37 ± 0.6 mm Hg and 7.49 ± 0.01, respectively. Arterial pH and Fe(Cl) - Fe(Na) were significantly correlated. We conclude that the kidney responds rapidly to acute respiratory acidosis, within 30 min of onset, by differential reabsorption of sodium and chloride.
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Affiliation(s)
- Jayanth Ramadoss
- Department of Veterinary Physiology and Pharmacology, Michael E. DeBakey Institute, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, 77843, USA
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Demirjian S, Teo BW, Guzman JA, Heyka RJ, Paganini EP, Fissell WH, Schold JD, Schreiber MJ. Hypophosphatemia during continuous hemodialysis is associated with prolonged respiratory failure in patients with acute kidney injury. Nephrol Dial Transplant 2011; 26:3508-14. [DOI: 10.1093/ndt/gfr075] [Citation(s) in RCA: 98] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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Abstract
Routine detection and treatment of acute hypophosphataemia is important in intensive care unit and many other hospitalized patients, but metabolic bone disease and hypophosphataemia are still experienced as a result of parenteral nutrition. A significantly common problem that faces the compounding pharmacist when formulating parenteral nutrition regimens is the difficulty associated with the successful avoidance of calcium phosphate precipitation. Although incorporation of the normal calcium and phosphate requirements into regimens for metabolically stable adults is usually achievable, it can prove impossible in paediatric and neonatal mixtures when using the standard inorganic sources that are currently licensed for use in the UK and USA. In other countries, where organic compounds are routinely available, this problem does not exist.
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Affiliation(s)
- W Hicks
- Department of Biochemistry, School of Biological and Molecular Sciences, University of Liverpool, Liverpool, UK
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CARTER NW, SELDIN DW, TENG HC. Tissue and renal response to chronic respiratory acidosis. J Clin Invest 2000; 38:949-60. [PMID: 13654532 PMCID: PMC293246 DOI: 10.1172/jci103878] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
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10
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LEVITIN H, BRANSCOME W, EPSTEIN FH. The pathogenesis of hypochloremia in respiratory acidosis. J Clin Invest 2000; 37:1667-75. [PMID: 13611033 PMCID: PMC1062852 DOI: 10.1172/jci103758] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
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HUTH EJ, SQUIRES RD, ELKINTON JR. Experimental potassium depletion in normal human subjects. II. Renal and hormonal factors in the development of extracellular alkalosis during depletion. J Clin Invest 2000; 38:1149-65. [PMID: 13664790 PMCID: PMC293262 DOI: 10.1172/jci103891] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
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OWEN EE, TYOR MP, GIORDANO D. The effect of acute alkalosis on renal metabolism of ammonia in cirrhotics. J Clin Invest 1998; 41:1139-44. [PMID: 14482894 PMCID: PMC291021 DOI: 10.1172/jci104566] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
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HUTCHIN P, McLAUGHLIN JS, HAYES MA. Renal response to acidosis during anesthesia and operation. I. The effect of acute dilutional hyponatremia on hydrogen ion and free water excretion during metabolic acidosis in anesthetized dogs. Ann Surg 1998; 154:9-28. [PMID: 13717042 PMCID: PMC1465855 DOI: 10.1097/00000658-196107000-00002] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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BARKER ES, ELKINTON JR, CLARK JK. Studies of the renal excretion of magnesium in man. J Clin Invest 1998; 38:1733-45. [PMID: 13796804 PMCID: PMC444141 DOI: 10.1172/jci103952] [Citation(s) in RCA: 82] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
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Bugg NC, Jones JA. Hypophosphataemia. Pathophysiology, effects and management on the intensive care unit. Anaesthesia 1998; 53:895-902. [PMID: 9849285 DOI: 10.1046/j.1365-2044.1998.00463.x] [Citation(s) in RCA: 79] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Routine detection and treatment of hypophosphataemia on the intensive care unit is commonplace. Hypophosphataemia has been associated with a multitude of clinical effects and there are many associations between correction of hypophosphataemia and improvement in symptoms. However, there is no evidence at present to support the routine correction of hypophosphataemia in the absence of clinical symptoms or signs.
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Affiliation(s)
- N C Bugg
- Department of Anaesthesia, St Mary's Hospital, London, UK
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MACKENZIE GJ, DAVIES SH, MASSON HB, WADE JD. CAUSES OF METABOLIC ACIDOSIS IN EXTRACORPOREAL CIRCULATION AT NORMOTHERMIA. Thorax 1996; 18:215-9. [PMID: 14064615 PMCID: PMC1018766 DOI: 10.1136/thx.18.3.215] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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Hirsch J, Schlatter E. K+ channels in the basolateral membrane of rat cortical collecting duct. Kidney Int 1995; 48:1036-46. [PMID: 8569065 DOI: 10.1038/ki.1995.387] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Affiliation(s)
- J Hirsch
- Westfälische Wilhelms-Universität Münster, Germany
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Schlatter E, Haxelmans S, Hirsch J, Leipziger J. pH dependence of K+ conductances of rat cortical collecting duct principal cells. Pflugers Arch 1994; 428:631-40. [PMID: 7838686 DOI: 10.1007/bf00374587] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
The K+ channels of the principal cells of rat cortical collecting duct (CCD) are pH sensitive in excised membranes. K+ secretion is decreased with increased H+ secretion during acidosis. We examined whether the pH sensitivity of these K+ channels is present also in the intact cell and thus could explain the coupling between K+ and H+ secretion. Membrane voltages (Vm), whole-cell conductances (gc), and single-channel currents of K+ channels were recorded from freshly isolated CCD cells or isolated CCD segments with the patch-clamp method. Intracellular pH (pHi) was measured using the pH-sensitive fluorescent dye 2'-7'-bis(carboxyethyl)-5-6-carboxyfluorescein (BCECF). Acetate (20 mmol/l) had no effect on Vm, gc, or the activity of the K+ channels in these cells. Acetate, however, acidified pHi slightly by 0.17 +/- 0.04 pH units (n = 19). Vm depolarized by 12 +/- 3 mV (n = 26) and by 23 +/- 2 mV (n = 66) and gc decreased by 26 +/- 5% (n = 13) and by 55 +/- 5% (n = 12) with 3-5 or 8-10% CO2, respectively. The same CO2 concentrations decreased pHi by 0.49 +/- 0.07 (n = 15) and 0.73 +/- 0.11 pH units (n = 12), respectively. Open probability (Po) of all four K+ channels in the intact rat CCD cells was reversibly inhibited by 8-10% CO2. pHi increased with the addition of 20 mmol/l NH4+/NH3 by a maximum of 0.64 +/- 0.08 pH units (n = 33) and acidified transiently by 0.37 +/- 0.05 pH units (n = 33) upon NH4+/NH3 removal. In the presence of NH4+/NH3 Vm depolarized by 16 +/- 2 mV (n = 66) and gc decreased by 26 +/- 7% (n = 16). The activity of all four K+ channels was also strongly inhibited in the presence of NH4+/NH3. The effect of NH4+/NH3 on Vm and gc was markedly increased when the pH of the NH4+/NH3-containing solution was set to 8.5 or 9.2. From these data we conclude that cellular acidification in rat CCD principal cells down-regulates K+ conductances, thus reduces K+ secretion by direct inhibition of K+ channel activity. This pH dependence is present in all four K+ channels of the rat CCD. The inhibition of K+ channels by NH4+/NH3 is independent of changes in pHi and rather involves an effect of NH3.
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Affiliation(s)
- E Schlatter
- Westfälische Wilhelms-Universität Münster, Germany
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Dias RM, Stabile C, Dotto P, Jardim JR. Intermittent negative pressure ventilation may increase urine flow in normal subjects. SAO PAULO MED J 1994; 112:551-4. [PMID: 7610325 DOI: 10.1590/s1516-31801994000200006] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
In order to analyze the effect of intermittent negative pressure ventilation (NPV) on renal function, we studied 20 healthy male volunteers (mean age 29 +/- 4.1 years). NPV was performed with an "Emerson Chest Respirator Pump", adjusted to a breathing frequency of 10 respirations per minute, with inspiratory time/total respiratory time ratio of 0.4 and negative pressure of 25 cmH2O. The experimental protocol was carried out in two phases of two hours each--spontaneous breathing and NPV breathing. At the end of each phase, urine volume of the whole period was collected as well as venous blood sample for biochemical determinations. During NPV there was significant increase (P < 0.05) in urine flow rate (1.43 +/- 0.81 to 2.76 +/- 1.95 ml/min) as well as in natriuresis (258 +/- 201 to 389 +/- 175 mcEq/min), kaliuresis (61 +/- 45 to 98 +/- 49 mcEq/min), fractional sodium excretion (1.38 +/- 0.88 to (1.96 +/- 0.98%), osmolar clearance (3.13 +/- 1.82 to 4.32 +/- 1.24 ml/min) and pH (7.37 +/- 0.04 to 7.41 +/- 0.07) with unchanged creatinine and free water clearances. We concluded that NPV increases urine flow rate, kaliuresis and natriuresis but the data we have do not allow us to explain the mechanisms underlying such a phenomenon.
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Affiliation(s)
- R M Dias
- Respiratory and Nephrology Divisions, Escola Paulista de Medicina, São Paulo
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al-Obaidi M, Whitaker EM, Karim F. The effect of discrete stimulation of carotid body chemoreceptors on atrial natriuretic peptide in anaesthetized dogs. J Physiol 1991; 443:519-31. [PMID: 1840408 PMCID: PMC1179857 DOI: 10.1113/jphysiol.1991.sp018849] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
1. In seven chloralose-anaesthetized and artificially ventilated beagles, the carotid sinus regions were vascularly isolated and perfused with either arterial or mixed (arterial and venous) blood (PO2 46.4 +/- 1.5 mmHg, mean +/- S.E.M.) to stimulate the chemoreceptors at constant flow and pressure. Cervical vagosympathetic trunks were ligated in all dogs, and gallamine triethiodide (2.0 mg kg-1 h-1, I.V.) was given in five dogs. Right atrial pressure was measured in all dogs, and left atrial pressure in four dogs. Mean aortic pressure was held constant (91.0 +/- 3.0 mmHg) by means of a reservoir connected to the animal via the common carotid and femoral arteries. Plasma atrial natriuretic peptide (ANP) was measured by radioimmunoassay and urinary sodium by flame photometry. 2. In seven dogs with mean carotid sinus pressure maintained at 96.0 +/- 4.3 mmHg, stimulation of the carotid chemoreceptors for 25 min produced significant increases in left atrial pressure of 41.2 +/- 3.3% (n = 4; P less than 0.005) from 5.4 +/- 0.6 cmH2O and of 30.9 +/- 4.5% (n = 7; P less than 0.002) in ANP from 31.6 +/- 2.1 pg ml-1. However, chemoreceptor stimulation produced significant decreases in urine flow rate of 26.1 +/- 1.9% (n = 9; P less than 0.001) from 0.29 +/- 0.03 ml min-1 (100 g kidney weight)-1 and sodium excretion of 29.0 +/- 2.3% (P less than 0.001) from 8.5 +/- 1.7 mumol min-1 (100 g kidney weight)-1 but right atrial pressure and heart rate did not change significantly. In three of the dogs, beta-adrenoceptor blockade by atenolol (2 mg kg-1, I.V.) greatly reduced the effects of chemoreceptor stimulation on plasma levels of ANP. 3. The results show, for the first time, that discrete stimulation of the carotid chemoreceptors caused an increase in plasma ANP levels, probably due to the reflex increase in atrial pressure that results from an inhibition of the cardiac sympathetic nerves, and an increase in venous return from a reduction of peripheral vascular capacitance.
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Affiliation(s)
- M al-Obaidi
- Department of Physiology, University of Leeds
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Krapf R, Beeler I, Hertner D, Hulter HN. Chronic respiratory alkalosis. The effect of sustained hyperventilation on renal regulation of acid-base equilibrium. N Engl J Med 1991; 324:1394-401. [PMID: 1902283 DOI: 10.1056/nejm199105163242003] [Citation(s) in RCA: 79] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
BACKGROUND In normal subjects, chronic hyperventilation lowers plasma bicarbonate concentration, primarily by inhibiting the urinary excretion of net acid. The quantitative relation between reduced arterial carbon dioxide tension (PaCO2) and the plasma bicarbonate concentration in the chronic steady state has not been studied in humans, however, and the laboratory criteria for the diagnosis of chronic respiratory alkalosis therefore remain undefined. We wished to provide such reference data for clinical use. Moreover, because chronic hyperventilation paradoxically lowers blood pH still further in dogs with metabolic acidosis, we desired to study the effect of chronic hypocapnia on the plasma bicarbonate concentration (and blood pH) in normal human subjects in whom acidosis had been induced with ammonium chloride. METHODS Under metabolic-balance conditions, we used altitude-induced hypobaric hypoxia to produce chronic hypocapnia in nine normal young men, five of whom received ammonium chloride daily to cause metabolic acidosis (the mean [+/- SE] steady-state plasma bicarbonate level in these five was 12.0 +/- 0.5 mmol per liter). RESULTS For each decrease of 1 mm Hg (0.13 kPa) in the PaCO2, the plasma bicarbonate concentration decreased by 0.41 mmol per liter in the subjects who started with a normal plasma bicarbonate concentration and by 0.42 mmol per liter in the subjects with acidosis. In contrast to the findings in previous studies of dogs, hypocapnia increased blood pH similarly in both groups; the blood hydrogen ion concentration decreased by about 0.4 nmol per liter for every decrease of 1 mm Hg (0.13 kPa) in PaCO2. CONCLUSIONS These results provide reference data for the diagnosis of chronic respiratory alkalosis in humans. Although chronic hypocapnia decreased plasma bicarbonate levels similarly in normal subjects with acidosis and without acidosis, the percent reduction in PaCO2 was always greater than the corresponding percent reduction in the plasma bicarbonate concentration. Therefore, as was not true of the response in dogs, the subjects' blood pH always increased with hyperventilation, regardless of the initial plasma bicarbonate concentration.
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Affiliation(s)
- R Krapf
- Department of Medicine, Insel University Hospital, Berne, Switzerland
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Rybczynska A, Berndt TJ, Hoppe A, Knox FG. Site of restoration of the effect of PTH by propranolol in respiratory alkalosis. Kidney Int 1990; 38:258-62. [PMID: 2402118 DOI: 10.1038/ki.1990.194] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Respiratory alkalosis decreases the phosphaturic response to parathyroid hormone (PTH). beta-adrenoreceptor blockade by propranolol infusion restores the phosphaturic effect of PTH in respiratory alkalotic rats; however, the nephron site of these changes in phosphate reabsorption by propranolol is not known. The present study was performed to localize the nephron segment(s) involved in the restoration of the phosphaturic effect of PTH by propranolol infusion in respiratory alkalotic rats. PTH infusion increased the fractional delivery of phosphate (FDPi) to the late proximal tubule to similar levels in the propranolol and vehicle-infused respiratory alkalotic rats (FDPi 46.6 +/- 4.4% and 48.6 +/- 4.2%, respectively). In contrast, PTH only increased FDPi to the early distal tubules (to 17.1 +/- 0.9%) in the absence of propranolol compared to FDPi 41.9 +/- 2.5% in the presence of propranolol in respiratory alkalotic animals. We conclude that the restoration of the phosphaturic effect of PTH in respiratory alkalotic rats by propranolol infusion is due primarily to decreased reabsorption of phosphate by the straight segment of the proximal tubule.
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Affiliation(s)
- A Rybczynska
- Department of Physiology and Biophysics, Mayo Medical School, Rochester, Minnesota
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Breyer MD, Kokko JP, Jacobson HR. Regulation of net bicarbonate transport in rabbit cortical collecting tubule by peritubular pH, carbon dioxide tension, and bicarbonate concentration. J Clin Invest 1986; 77:1650-60. [PMID: 3084564 PMCID: PMC424570 DOI: 10.1172/jci112482] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
The effects of changes in peritubular pH, carbon dioxide tension (PCO2), and HCO3- concentration on net HCO3- transport was examined in in vitro perfused cortical collecting tubules (CCTs) from unpretreated New Zealand white rabbits. Lowering peritubular HCO3- concentration and pH by reciprocal replacement of HCO3- with Cl-, significantly stimulated net HCO3- absorption. Lowering peritubular HCO3- concentration and pH, by substitution of HCO3- with gluconate, while keeping Cl- concentration constant, also stimulated net HCO3- absorption. Raising peritubular HCO3- concentration and pH, by reciprocal replacement of Cl- with HCO3-, inhibited net HCO3- absorption (or stimulated net HCO3- secretion). When the tubule was cooled, raising peritubular HCO3- concentration had no effect on net HCO3- transport, suggesting these results are not due to the passive flux of HCO3- down its concentration gradient. The effect of changes in ambient PCO2 on net HCO3- transport were also studied. Increasing the ambient PCO2 from 40 mmHg to either 80 or 120 mmHg, allowing pH to fall, had no effect on net HCO3- transport. Similarly, lowering ambient PCO2 to 14 mmHg had no effect on net HCO3- transport. Simultaneously increasing peritubular HCO3- concentration and PCO2, without accompanying changes in peritubular pH, i.e., isohydric changes, stimulated net HCO3- secretion to the same degree as nonisohydric increases in peritubular HCO3- concentration. Likewise, isohydric lowering of peritubular HCO3- concentration and PCO2 stimulated net HCO3- absorption. We conclude that: acute changes in peritubular HCO3- concentration regulate acidification in the CCT and these effects are mediated by a transcellular process; acute changes in ambient PCO2 within the physiologic range have no effect on HCO3- transport in the in vitro perfused CCT; and acute in vitro regulation of CCT acidification is independent of peritubular pH.
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Batlle DC, Downer M, Gutterman C, Kurtzman NA. Relationship of urinary and blood carbon dioxide tension during hypercapnia in the rat. Its significance in the evaluation of collecting duct hydrogen ion secretion. J Clin Invest 1985; 75:1517-30. [PMID: 2987305 PMCID: PMC425491 DOI: 10.1172/jci111856] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
This study was designed to establish the relationship between urinary pCO2 and systemic blood pCO2 during acute hypercapnia and to investigate the significance of this relationship to collecting duct hydrogen ion (H+) secretion when the urine is acid and when it is highly alkaline. In rats excreting a highly alkaline urine, an acute increase in blood pCO2 (from 42 +/- 0.8 to 87 +/- 0.8 mmHg) resulted in a significant fall in urine minus blood (U-B) pCO2 (from 31 +/- 2.0 to 16 +/- 4.2 mmHg, P less than 0.005), a finding which could be interpreted to indicate inhibition of collecting duct H+ secretion by hypercapnia. The urinary pCO2 of rats with hypercapnia, unlike that of normocapnic controls, was significantly lower than that of blood when the urine was acid (58 +/- 6.3 and 86 +/- 1.7 mmHg, P less than 0.001) and when it was alkalinized in the face of accelerated carbonic acid dehydration by infusion of carbonic anhydrase (78 +/- 2.7 and 87 +/- 1.8 mmHg, P less than 0.02). The finding of a urinary pCO2 lower than systemic blood pCO2 during hypercapnia suggested that the urine pCO2 prevailing before bicarbonate loading should be known and the blood pCO2 kept constant to evaluate collecting duct H+ secretion using the urinary pCO2 technique. In experiments performed under these conditions, sodium bicarbonate infusion resulted in an increment in urinary pCO2 (i.e., a delta pCO2) which was comparable in hypercapnic and normocapnic rats (40 +/- 7.2 and 42 +/- 4.6 mmHg, respectively) that were alkalemic (blood pH 7.53 +/- 0.02 and 7.69 +/- 0.01, respectively). The U-B pCO2, however, was again lower in hypercapnic than in normocapnic rats (15 +/- 4.0 and 39 +/- 2.5 mmHg, respectively, P less than 0.001). In hypercapnic rats in which blood pH during bicarbonate infusion was not allowed to become alkalemic (7.38 +/- 0.01), the delta pCO2 was higher than that of normocapnic rats which were alkalemic (70 +/- 5.6 and 42 +/- 4.6 mmHg, respectively, P less than 0.005) while the U-B pCO2 was about the same (39 +/- 3.7 and 39 +/- 2.5 mmHg). We further examined urine pCO2 generation by measuring the difference between the urine pCO2 of a highly alkaline urine not containing carbonic anhydrase and that of an equally alkaline urine containing this enzyme. Carbonic anhydrase infusion to hypercapnic rats that were not alkalemic resulted in a fall in urine pCO(2) (from 122+/-5.7 to 77+/-2.2 mmHg) which was greater (P <0.02) than that seen in alkalemic normocapnic controls (from 73+/- 1.9 to 43+/-1.3 mmHg) with a comparable urine bicarbonate concentration and urine nonbicarbonate buffer capacity. CO(2) generation, therefore, from collecting dust H(+) secretion and titration of bicarbonate, was higher in hypercapnic rats that in normocapnic controls. We conclude that in rats with actue hypercapnia, the U-B p(CO(2)) achieved during bicarbonate loading greatly underestimates collecting duct H(+) secretion because it is artificially influenced by systemic blood pCO(2). the deltapCO(2) is a better qualitative index of collecting duct H+ secretion that the U-B pCO(2), because it is not artificially influenced by systemic blood pCO(2) and it takes into account the urine PCO(2) prevailing before bicarbonate loading.
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Hansen AC, Wamberg S, Engel K, Kildeberg P. Balance of net base in the rat: adaptation to and recovery from sustained hypercapnia. Scand J Clin Lab Invest 1979; 39:723-30. [PMID: 531494 DOI: 10.1080/00365517909108163] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Net base and mineral balances were evaluated in a group of male 350 g Wistar rats exposed to 10% carbon dioxide in air for 10 days with a view to identifying the source of net base subject to retention during renal compensation of sustained respiratory acidosis. In response to hypercapnia, the rate of renal net acid excretion rose but insignificantly. However, a rise in whole body net base concentration from about 215 mmol/kg to about 250 mmol/kg came about by ongoing gastrointestinal absorption in the weight-losing animal, absorbed net base being distributed to extracellular and non-extracellular compartments of the body, presumably including bone. During an 8-day recovery period, a small decrement in whole body net base concentration was observed.
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Gallery E, Györy A, Lissner D, Timbs SR. Urinary concentration, white blood cell excretion, acid excretion, and acid-base status in normal pregnancy: Alterations in pregnancy-associated hypertension. Am J Obstet Gynecol 1979. [DOI: 10.1016/s0002-9378(79)80012-5] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Webb RK, Woodhall PB, Tisher CC, Glaubiger G, Neelon FA, Robinson RR. Relationship between phosphaluria and acute hypercapnia in the rat. J Clin Invest 1977; 60:829-37. [PMID: 19498 PMCID: PMC372431 DOI: 10.1172/jci108837] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Standard clearance studies were performed in mechanically ventilated intact and acutely thyroparathyroidectomized (TPTX) rats to document and characterize the effect of hypercapnia (HC) on urinary phosphorus excretion (U(P)V). HC as compared to normocapnia (NC) was associated with an increase in U(P)V in intact (62.5 vs. 7.93 mug/min) and TPTX (30.5 vs. 0.59 mug/min) rats, an increase in filtered load of phosphorus in intact (218 vs. 191 mug/min) and TPTX (243 vs. 146 mug/min) rats, an increase in blood bicarbonate concentration in intact (27.8 vs. 26.0 meq/liter) and TPTX (24.5 vs. 22.3 meq/liter) animals, and a decrease in blood pH in intact (7.15 vs. 7.42) and TPTX (7.07 vs. 7.39) rats. Additional TPTX rats with NC and HC were studied during phosphorus infusion at a comparable filtered load of phosphorus (NC = 307 mug/min and HC = 328 mug/min). U(P)V was 18.5 mug/min in NC and 85.2 mug/min in HC animals. Intact NC animals infused with NaHCO(3) achieved a blood bicarbonate of 45.9 meq/liter compared to 26.0 meq/liter in intact NC NaCl-infused rats. U(P)V was 10.0 mug/min in the NaHCO(3) and 7.93 mug/min in NaCl-infused animals. In intact HC animals infused with NaHCO(3), blood pH was 7.36 compared to 7.42 in NC intact NaCl-infused animals. U(P)V was 83.2 mug/min in the HC bicarbonate-infused and 7.93 mug/min in the NC NaCl-infused rats. These experiments demonstrate that elevated blood carbon dioxide tension per se increases U(P)V. Increases in filtered load of phosphorus and blood bicarbonate which are associated with HC contribute to the phosphaturia as does parathyroid hormone. The phosphaturia is not dependent upon reduction of extracellular pH.
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Giammarco RA, Goldstein MB, Halperin ML, Stinebaugh BJ. The effect of hyperventilation on distal nephron hydrogen ion secretion. J Clin Invest 1976; 58:77-82. [PMID: 6492 PMCID: PMC333157 DOI: 10.1172/jci108462] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
This study was designed to determine the effect of acute hyperventilation on distal nephron hydrogen ion secretion. The blood PCO2 declined and stabilized rapidly when bicarbonate loaded rats were hyperventilated. In contrast, the urine PCO2 declined slowly, resulting in an early increase in the urine minus blood (U-B) PCO2 which could not be obliterated by carbonic anhydrase infusion. Within approximately 50 min, the U-B PCO2 in the hyperventilated and carbonic anhydrase infused rats approached zero. Consequently, equilibrium between collecting duct urine and arterial blood PCO2 was then presumed to exist. This provided the basis for the subsequent studies on a series of rats. The U-B PCO2 decreased from a control of 22+/-1 mm Hg (mean+/-SEM) to 11+/-2 mm Hg (mean+/-SEM) with hypocapnia, and rose again to its control value when the blood PCO2 returned to prehyperventilation values. This decline in U-B PCO2 with acute hyperventilation could not be attributed to changes in urine flow, phosphate, or bicarbonate excretion, suggesting, therefore, a decrease in distal nephron (probably collecting duct) hydrogen ion secretion with acute hyperventilation. Possible pitfalls in the interpretation of the UB PCO2 are illustrated.
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Abstract
This study examines the renal response to moderate hyperventilation in healthy man. Eight men hyperventilated for 26 hr (PaCO2 approximately 30 to 32 mm Hg) in normoxia (barometric pressure, PB approximately 740 mm Hg) and hypobaric hypoxia (PB approximately530 mm Hg). Anaerobic samples of arterial blood and urine were studied at two-hour intervals. Plasma [HCO3-] fell with time during sustained hypocapnia and after 26 hr was reduced 2.5 mEq/liter, with plasma pH compensated approximately 60%. Statistically significant changes in renal H+ handling were observed within the initial 2 hr of hyperventilation and were evident over the first 12 hr. Over 26 hr, mean total HCO3-excretion in hypocapnia was 10.2 mEq above control and mean total acid excretion (UVTA + UVNH4+) was 17.5 mEq below control. An increased urinary excretion of cations, especially sodium, accompanied the decrease in acid excretion. Plasma lactic acid accumulation was negligible. We conclude that renal mechanisms contribute significantly and relatively quickly to plasma pH compensation during the early phase of adaptation to hypocapnia in man.
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Gennari FJ, Cohen JJ. Role of the kidney in potassium homeostasis: lessons from acid-base disturbances. Kidney Int 1975; 8:1-5. [PMID: 240056 DOI: 10.1038/ki.1975.69] [Citation(s) in RCA: 47] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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Spitzer A, Edelmann CM, Goldberg LD, Henneman PH. Short stature, hyperkalemia and acidosis: A defect in renal transport of potassium. Kidney Int 1973; 3:251-7. [PMID: 4792041 DOI: 10.1038/ki.1973.38] [Citation(s) in RCA: 62] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
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Gennari FJ, Goldstein MB, Schwartz WB. The nature of the renal adaptation to chronic hypocapnia. J Clin Invest 1972; 51:1722-30. [PMID: 5032522 PMCID: PMC292319 DOI: 10.1172/jci106973] [Citation(s) in RCA: 82] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
Metabolic balance studies were carried out in normal dogs to define the renal mechanisms responsible for the adaptation to, and recovery from, chronic hypocapnia. A chronic reduction in arterial CO(2) tension (Pa(CO2)) of some 15 mm Hg was achieved by means of chronic exposure of the animals to 9% oxygen in an environmental chamber. The development of hypocapnia was associated with a marked suppression of net acid excretion which, together with a slight accumulation of organic acids, produced a reduction in plasma bicarbonate concentration (8 mEq/liter) that led to nearly full protection of extracellular pH (DeltaH(+) = - 2.5 nmoles/liter). When Pa(CO2) was returned to control levels, an augmentation of acid excretion restored plasma composition to normal after a brief period of "posthypocapneic metabolic acidosis."The changes in renal acid excretion during both adaptation and recovery were accomplished in a fashion notably different from that previously observed in chronic hypercapnia, being linked to changes in cation rather than chloride excretion. Thus, in dogs ingesting a normal NaCl diet, suppression of hydrogen ion excretion during adaptation to hypocapnia was associated with an increased excretion of sodium rather than with a retention of chloride. The fact that this loss of sodium occurred without a concomitant loss of potassium strongly suggests that the hypocapneic state specifically depressed distal sodium reabsorption; if distal sodium reabsorption had not been depressed, a reduction in proximal sodium reabsorption or a diminution in distal hydrogen ion secretion (or both) should have produced an increase in potassium excretion. The interpretation that chronic hypocapnia diminished sodium reabsorption was supported by the finding that when renal sodium avidity was enhanced by restriction of sodium intake, acid retention was accomplished by a loss of potassium rather than of sodium. The accompanying reduction in plasma bicarbonate concentration was slightly less than that observed in dogs ingesting a normal NaCl diet, a finding probably accounted for by a slight difference in the availability of cation for excretion under the two experimental circumstances. These findings, taken together with the observation that augmented acid excretion during recovery from hypocapnia is linked to cation retention, suggest that an adequate intake of cation during both adaptation and recovery from chronic hypocapnia may be critical to the physiologic regulation of acid-base equilibrium.
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Trimble C, Smith DE, Rosenthal MH, Fosburg RG. Pathophysiologic role of hypocarbia in post-traumatic pulmonary insufficiency. Am J Surg 1971; 122:633-8. [PMID: 5112069 DOI: 10.1016/0002-9610(71)90291-1] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
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Arbus GS, Herbert LA, Levesque PR, Etsten BE, Schwartz WB. Characterization and clinical application of the "significance band" for acute respiratory alkalosis. N Engl J Med 1969; 280:117-23. [PMID: 5782512 DOI: 10.1056/nejm196901162800301] [Citation(s) in RCA: 81] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
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Clark GF. Relationship of metabolic acidosis and capillary pco2 in cyclopropane and halothane anaesthesia. Can J Anaesth 1967. [DOI: 10.1007/bf03004054] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
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Ghose RR. The significance of acid-base measurements in the management of salicylate intoxication. Postgrad Med J 1967; 43:454-7. [PMID: 6041637 PMCID: PMC2466326 DOI: 10.1136/pgmj.43.501.454] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
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Downes JJ, Striker TW. Acute respiratory failure in infants and children with bronchiolitis, pneumonitis and status astmaticus. ACTA ANAESTHESIOLOGICA SCANDINAVICA. SUPPLEMENTUM 1966; 23:747-57. [PMID: 5251853 DOI: 10.1111/j.1399-6576.1966.tb01091.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
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Connolly JE, Kountz SL, Guernsey JM, Stemmer EA. ACIDOSIS AS A CAUSE OF RENAL SHUTDOWN DURING EXTRACORPOREAL CIRCULATION: ITS CORRECTION BY THE USE OF THAM. J Thorac Cardiovasc Surg 1963. [DOI: 10.1016/s0022-5223(19)33640-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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HUTCHIN P, McLAUGHLIN JS, HAYES MA. Renal response to acidosis during anesthesia and operation. III. Maintenance of homeostasis in acute respiratory acidosis during intravenous infusion of Ringer's Lactate and 5 percent glucose in water. Ann Surg 1961; 154:161-80. [PMID: 13717044 PMCID: PMC1465873 DOI: 10.1097/00000658-196108000-00002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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ELKINTON JR, HUTH EJ, WEBSTER GD, McCANCE RA. The renal excretion of hydrogen ion in renal tubular acidosis. I. quantitative assessment of the response to ammonium chloride as an acid load. Am J Med 1960; 29:554-75. [PMID: 13726399 DOI: 10.1016/0002-9343(60)90090-5] [Citation(s) in RCA: 93] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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WEBSTER GD, HUTH EJ, ELKINTON JR, McCANCE RA. The renal excretion of hydrogen ion in renal tubular acidosis. II. Quantitative response to the carbonic anhydrase inhibitor, acetazolamide. Am J Med 1960; 29:576-85. [PMID: 13783654 DOI: 10.1016/0002-9343(60)90091-7] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Magovern GJ, Cartwright RS, Neville JF, Kent EM. METABOLIC ACIDOSIS AND THE DISSOCIATION CURVE OF HEMOGLOBIN DURING EXTRACORPOREAL CIRCULATION. J Thorac Cardiovasc Surg 1959. [DOI: 10.1016/s0022-5223(19)32419-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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